Laptop Mode Tools is a laptop power saving package for Linux systems. It allows you to extend the battery life of your laptop, in several ways. It is the primary way to enable the Laptop Mode feature of the Linux kernel, which lets your hard drive spin down. In addition, it allows you to tweak a number of other power-related settings using a simple configuration file.

To install, run ./install.sh. That's all there's to it. This will install
laptop mode, which will be enabled automatically when your laptop works
on batteries. Debian users, please install the Debian package that can
be found on the home page and in the unstable repository!